Major Sedimentary Basins in India.
India has an estimated sedimentary area of 3.36 million sq km. comprising of 26 sedimentary basins, out of which, 1.63 million sq km. area is in on-land, shallow offshore up-to 400m isobath have an areal extent of 0.41 million sq km. and deep-water beyond 400m isobath having sedimentary area of 1.32 million sq km. area as per renewed categorisation of sedimentary basins.
Over the last few years, there have been a significant forward leap in exploring the hydrocarbon potential of the sedimentary basins of India. The unexplored area has come down significantly as a result of the surveys carried out by DGH in unexplored/poorly explored areas of the country including Deep-waters and acreages awarded for exploration under NELP/OALP rounds. Concerned efforts are continuously being done to reduce the unexplored area further.
These 26 Indian sedimentary basins have been divided into three categories based on their degree of prospectivity.
On the basis of prospectivity basins have been categorised as follows:
Category I : (Basins with reserves being produced and potential to be exploited at increased recovery)
| Basin Name | Area On-land | Area Shallow-water | Area Deep-water | Area Total |
|---|---|---|---|---|
| Krishna-Godawari | 31,456 | 25,649 | 1,72,895 | 2,30,000 |
| Mumbai Offshore | – | 1,18,389 | 93,611 | 2,12,000 |
| Assam Shelf | 56,000 | – | – | 56,000 |
| Rajasthan | 1,26,000 | – | – | 1,26,000 |
| Cauvery | 37,825 | 43,723 | 1,58,452 | 2,40,000 |
| Assam-Arakan Fold Belt | 80,825 | – | – | 80,825 |
| Cambay | 48,882 | 4,618 | – | 53,500 |
Category II : Basins with contingent resources to be developed and produced
| Basin Name | Area Onland | Area Shallowwater | Area Deepwater | Area Total |
|---|---|---|---|---|
| Saurashtra | 75,076 | 42,617 | 76,421 | 1,94,114 |
| Kutch | 30,754 | 20,500 | 7,300 | 58,554 |
| Vindhyan | 2,02,888 | – | – | 2,02,888 |
| Mahanadi | 15,500 | 14,211 | 69,789 | 99,500 |
| Andaman-Nicobar | – | 18,074 | 2,07,844 | 2,25,918 |
Category III : Basins with only prospective resources to be explored and discovered
| Basin Name | Area Onland | Area Shallowwater | Area Deepwater | Area Total |
|---|---|---|---|---|
| Kerala-Konkan | – | 90,380 | 4,89,620 | 5,80,000 |
| Bengal-Purnea | 42,414 | 33,465 | 46,035 | 1,21,914 |
| Ganga Punjab | 3,04,000 | – | – | 3,04,000 |
| Pranhita Godavari | 30,000 | – | – | 30,000 |
| Satpura-S.Rewa-Damodar | 57,180 | – | – | 57,180 |
| Himalyan Foreland | 30,110 | – | – | 30,110 |
| Chhattisgarh | 32,000 | – | – | 32,000 |
| Narmada | 95,215 | – | – | 95,215 |
| Spiti Zanskar | 32,000 | – | – | 32,000 |
| Deccan Syneclise | 2,37,500 | – | – | 2,37,500 |
| Cuddapah | 40,100 | – | – | 40,100 |
| Karewa | 6,671 | – | – | 6,671 |
| Bhima Kaladgi | 14,100 | – | – | 14,100 |
| Bastar | 5,360 | – | – | 5,360 |